Amines
REACH
o-Tolidine
CAS Number
119-93-7
EC Number
204-358-0
Abbreviation
DMB
What is o-Tolidine?
o-Tolidine (CAS 119-93-7), also known commercially as 3,3'-dimethylbenzidine or DMB, is an aromatic diamine used as a chemical intermediate in the production of dyes, pigments, and curing agents.
Where is o-Tolidine used?
- Dye and pigment industry: key intermediate
- Diazo-based yellow and orange pigments for printing inks and packaging colorants
- Textile and leather: DMB-derived dyes for high-fastness coloration on natural and synthetic substrates
- Polymer and elastomer manufacturing: curing agent for polyurethane and polyurea systems where controlled crosslink density is required
- Specialty coatings: precursor for performance pigments with strong lightfastness characteristics
- Its bifunctional amine structure makes it a reactive building block for synthesizing azo colorants and polyurea-based systems.
Commercial specifications
- Bulk quantities suited to pigment manufacturers and polymer processors
- Packaging: drums to bulk bags depending on volume requirements and logistical needs
Other Names (Synonyms)
3,3'-dimethylbenzidine|4-(4-amino-3-methylphenyl)-2-methylaniline|DMB
What are the physical properties of o-Tolidine?
Melting Point 129-131 °C
Boiling Point 300 °C
Density 1.234 g/cm³
Flash Point 244 °C
Appearance o-Tolidine is a white to reddish crystal or powder. Darkens on exposure to air. Often used in paste or wet cake form. Used as a basis for many dyes.
Color light brown
Form powder (may contain lumps)
Water Solubility Slightly soluble in water.
Refractive Index n 20/D 1.341
How is o-Tolidine classified and handled safely? Learn More
Danger
GHS07· Irritant GHS08· Health Hazard GHS09· Environmental Hazard
Hazard Statements
H302 Harmful if swallowed
H341 Suspected of causing genetic defects
H350 May cause cancer
H351 Suspected of causing cancer
Precautionary Statements
P203 Obtain, consult and follow expert instructions for use.
P260 Do not breathe dust/fume/gas/mist/vapours/spray.
P264 Wash … thoroughly after handling.
P270 Do not eat, drink or smoke when using this product.
Which trade and regulatory codes apply to o-Tolidine?
HS Code 29215900
UN Number 3082
ADR Class 9
Packing Group III
Storage Class 6.1C - Combustible acute toxic Cat.3
toxic compounds or compounds which causing chronic effects
WGK (Germany) 3